1. Technical Field
The present invention relates to a method of manufacturing an inorganic oxide film, to an electronic device substrate, to a method of manufacturing an electronic device substrate, to a liquid crystal panel, and to an electronic apparatus.
2. Related Art
In recent years, vertical-alignment-type liquid crystal display devices have been used for liquid crystal televisions (direct-view-type display apparatuses) and liquid crystal projectors (projection display apparatuses).
For example, organic alignment films formed of polyimide and oblique deposition films (inorganic oxide films) formed of, for example, SiO2 are generally used as the vertical alignment films of the vertical-alignment-type liquid crystal display devices. More specifically, the organic alignment films are used for the liquid crystal televisions, and the oblique deposition films are used for the liquid crystal projectors.
The oblique deposition film made of an inorganic oxide has a plurality of pores, and a plurality of polarized hydroxyl groups exist on the surface of the oblique deposition film and the inner surfaces of the pores. This hydroxyl group has activity as a Broensted acid, and is apt to absorb or react with liquid crystal molecules or impurities contained in a liquid crystal display device, particularly, a compound having a polar group.
The following are included in the impurities: impurities and unreacted ingredients contained in a sealing material; impurities and water contained in a liquid crystal layer; and dust generated from the manufacturing process.
It has been known that, when impurities are stuck onto or react with the surface of the oblique deposition film, the shape or polarity of the surface is changed to cause vertical anchoring force to be weakened, which results in the abnormal alignment of the liquid crystal molecules. In this case, it has also been known that the liquid crystal molecules directly react with the hydroxyl group.
Therefore, a method of treating the surface of the oblique deposition film (inorganic oxide film) with a higher alcohol or a silane coupling agent has been proposed as a method of reforming the surface of the oblique deposition film (for example, see JP-A-11-160711 and JP-A-5-203958).
In the method disclosed in JP-A-11-160711, an oblique deposition film formed of SiO2 is exposed to vapor of a higher alcohol.
Therefore, in this method, since a processing temperature is low, the higher alcohol is just physically stuck to the oblique deposition film, which results in excessively weak bonding force. Thus, when coming into contact with the liquid crystal molecules, the higher alcohol is easily separated from the surface of the oblique deposition film, which makes it difficult to obtain stable vertical alignment force in an initial state.
Further, in the method disclosed JP-A-5-203958, octadecyl dimethyl(3-(trimethoxysilyl)propyl)ammonium chloride, which is a silane coupling agent, is applied (comes into contact) as a vertical alignment agent on the oblique deposition film formed of SiO2 which is deposited under the assistance of ion beams. Then, the oblique deposition film is baked at a temperature of 110° C. for one hour.
However, in this case, the pores (openings) have a small diameter, and the mere contact between the silane coupling agent and the oblique deposition film causes only the hydroxyl group on the surface to be chemically bonded. That is, it is difficult to chemically bond the silane coupling agent to the hydroxyl group existing in the pores.
Therefore, the method disclosed in JP-A-5-203958 has a problem in that the alignment of the liquid crystal molecules is deteriorated in a relatively short time due to the influence of the hydroxyl group existing in the pores of the oblique deposition film.